Apparatus for producing open-topped hollow articles

ABSTRACT

An impact extruder comprising means for feeding circular workpieces of a metal, a turn table having a plurality of dies and ramming mechanisms supporting vertically movable punches in axial alignment with the dies, respectively, a ramming roll for downwardly driving the ramming mechanisms to cause the phnches to cooperate with associated dies to form the work-pieces into opentopped hollow articles during rotation of the turn table, a cam member for lifting the ramming mechanisms after their forming operations, and strippers for removing the formed articles from the punches.

United States Patent Mori et al. [4 1 June 20, 1972 s41 APPARATUS FOR PRODUCING OPEN- [56] References emu TOPPED HOLLOW ARTICLES UNITED STATES PATENTS [721 Inventors: Kazu -o Mort. Hirakata; Aldo n. 3,518,866 7/1970 Corrov ..72/36l Kyoto; Mlyoji Nukal, Neyagawa; Tetuji K Mol'iguchi, all of Japan Primary Examiner-Charles W. Lanham Matsushita Electric Industrial Co. Ltd. 145mm n R01!ms [73] Assign Osaka, Japan Attorney-Stevens, Davis, Miller8zMosher [22] Filed: Dec. 17, 1970 57 A ST CT PP 99,072 An impact extruder comprising means for feeding circular work-pieces of a metal, a turn table having a plurality of dies [30] Foreign Appufluon P i it and ramming mechanisms supporting vertically movable punches in axial alignment with the dies, respectively. a Dec. 22, i969 Japan ..44/ 104639 ramming 10" for downwardly driving the ramming mechanisms to cause the phnches to cooperate with as- [52] US. Cl ..72/l87, 72/346, 72/359 sedated dies to form the workpieces imo opemmpped hone, [51] Int. Cl. ..B2lb 1/04, 821d 45/00 articles during rotation of the mm table a cam member for [58] Field of Search ..72/l87, 193.257, lifting the ramming mechanisms after the, forming ovenb 72/359 36 tions, and strippers for removing the formed articles from the I punches.

7 Claims, 19 Drawing Figures ith PATENTEDJM 0 I972 3, 6 T0 548 sum 02 or 10 PATENTEDJum 1972 3,670,548

sum 03 or 10 P'A'TENTEDJum I972 SHEET 0 4 OF 10 PATENTEDJUH 2 0 I972 sum 'OSUF 1o PATENTEDmzo I972 3.670.548

sum 07 nr 10 PATENTEDauxzo 1972 3, 670 i 548 sum 10 0F 10 APPARATUS FOR PRODUCING OPEN-TOPPED HOLLOW ARTICLES BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to an apparatus comprising a plurality of sets of rotatable presses each having die and punch which cooperate together to produce open-topped hollow articles at a high speed from circular workpieces of a metal supplied by feeding means. Particularly, the invention is concerned with an apparatus of the above-mentioned kind and which is designed to be suited for the mass-production of opened-topped cylindrical hollow articles such as zinc casings for dry cells and aluminum housings for capacitors and the like.

It is a primary object of the present invention to provide an apparatus for successively producing such hollow articles at an increased efficiency from circular workpieces (hereafter termed billets") of a metal, which apparatus employs a plurality of presses or ramming mechanisms each required to be actuated for forward or working strokes only and not necessarily needed to be driven for rearward or article-removing strokes.

It is another object of the present invention to provide an apparatus of the above-specified class which employs sets of rotary type presses mounted on a turn table for rotation therewith and means for acculately and successively delivering billets from a hopper in aligned relationship with each other and for feeding the billets onto the turn table at a predetermined position.

It is a further object of the present invention to provide an apparatus of the above-specified class which employs a ramming roll for downwardly driving the ramming mechanisms and means operable to finely adjust the height of the ramming roll for thereby finely adjusting or shifting the range within which ramming mechanisms are actuated to have working strokes on which the shape of worked hollow articles depends.

It is a still further object of the present invention to provide an apparatus of the aforestated kind which employs stripper means for removing worked hollow articles from the punches, said stripper means having simplified construction for ensuring easy removal of worked articles from the punches and easy detachment of worn punches from punch holders for replacement of the worn punches with new ones.

It is a still further object of the present invention to provide an apparatus of the above-specified class which employs means for at least partly supporting the ramming mechanisms of the rotary type presses so that the ramming mechanisms have decreased resistance to vertical movements by other actuating means during operation of the apparatus or by manual operation for the replacement of punches.

It is a still further object of the present invention to provide an apparatus of the kind above-stated which employs means for precisely and easily adjusting the positions of respective dies with respect to corresponding punches so that finished hollow articles have precisely controlled wall thickness.

It is a still further object of the present invention to provide an apparatus of the aforestated class which is designed such that the heads of the ramming mechanisms which have been worn after operation for a certain amount of time may be easily dealt with.

SUMMARY OF INVENTION According to the present invention, there is provided an apparatus for producing open-topped hollow articles from circular work-pieces of a metal, comprising a turn table having a plurality of dies mounted thereon adjacent the periphery of said turn table by means of die position adjusting means, said turn table also having ramming mechanisms each having a punch disposed above one of said dies for cooperation therewith, a turret for receiving such workpieces supplied from a hopper by feeding means and for successively feeding the received work-pieces to said turn table, a ramming roll for downwardly moving said ramming mechanisms to cause said punches to cooperate with corresponding dies to form said workpieces therein into open-topped hollow articles during rotation of said turn table, cam means for lifting the ramming mechanisms after their forming operations, and stripper means each comprising a stripper for removing a formed hollow article from an associated punch.

The above and other objects and features of the invention will be made apparent from the following description of a preferred embodiment.

DESCRIPTION OF DRAWINGS FIG. 1 is a perspective view of the apparatus for producing hollow articles from billets according to an embodiment of the present invention; I

FIG. 2 is a schematic view illustrating the series of steps of process carried out in the apparatus shown in FIG. 1 in which the billets are fed and formed into hollow articles which are finally delivered;

FIG. 3 is a vertical section side elevation of the apparatus shown in FIG. 1;

FIG. 4 is a schematic perspective view illustrating the power-driving connections employed in the apparatus;

FIG. 5 is a fragmentary perspective view of the principal sections of billet feeding means with a part broken away;

FIG. 6 is an enlarged front elevational view of the billet feeding means shown in FIG. 5 with a part broken away;

FIG. 7 is an enlarged elevational side view of the means shown in FIG. 5 with a part shown in section;

FIG. 8 is a schematic perspective illustration of means for adjusting the height of ramming roll;

FIG. 9 is an enlarged partially sectional side view of the means for adjusting the height of ramming roll shown in FIG.

FIG. 10 is a fragmentary sectional view of the adjusting means of FIG. 8 illustrating the meshing engagement between gears for the ramming roll;

FIG. 11 is a fragmentary vertical sectional view of the apparatus illustrating a stripper for removing formed articles from a punch;

FIG. 12 is a cross-sectional view taken along line X X in FIG. 11;

FIG. 13 is a sectional view similar to FIG. 11 but illustrating the punch which is being drawn out of the stripper;

FIG. 14 is a fragmentary sectional view of the apparatus illustrating means for adjusting dies;

FIG. 15 is a partially sectional top plan view of the die adjusting means shown in FIG. 14;

FIG. 16 is a fragmentary vertical sectional view of the ramming head of a ramming mechanism;

FIG. 17 is a top plan view of the ramming head shown in FIG. 16;

FIG. 18 is a perspective view of the ramming head shown in FIG. 16; and

FIG. 19 illustrates a punch in difierent positions taken thereby during the process of working a billet to form a hollow article.

DESCRIPTION OF A PREFERRED EMBODIMENT The present invention provides a so-called impact extrusion apparatus for working pieces of metal or billets 1 into cylindrical hollow articles 1 by subjecting the billets to instantaneous impact by means of pairs of punch 2 and die 3 as shown in FIG. 19.

In the apparatus for manufacturing hollow articles from billets, the punches of the apparatus generally operate fairly well to work the billets when the following requirement is satisfied:

S a b wherein S is the stroke of punches when in the working of billets, a is the thickness of the billets and b is the thickness of the bottoms of worked or shaped hollow articles. However, the punches are required to have their retracting or backward stroke S which is greater than the height or longitudinal dimension of formed hollow articles 1' in order that the articles may be removed away from the cooperating pairs of punches and dies, as will be appreciated from the diagrammatic illustration of FIG. 19.

I-Ieretofore, these requirements have been taken into consideration in the design of conventional apparatuses of this kind sothat the punches are provided with excessive amount of stroke, i.e., more than the dimension as represented by S in FIG. 19 for the performance of both of the working of the billets and removal of worked hollow articles. The pressing or extrusion apparatus of the above-mentioned design is generally of the type of so-called crank press having punches fixed to rams which are reciprocally moved by the rotation of a crank shaft. The rams are designed to have larger amount of reciprocated movements which produce greater inertia. The conventional apparatus, therefore, is required to employ a bulky or large-sized machine frame and ram-supporting guides so that the apparatus has a substantial mechanical strength for withstanding the greater inertia and well absorbing the vibration during operation.

The present invention contemplates an apparatus of the above-mentioned kind which is free from the above-discussed short-comings and achieves the above objects of the invention.

Referring now to FIGS. 1 and 2 of the drawings, the apparatus according to one embodiment of the present invention is generally indicated by 10 and has a machine frame 20 on the top of which is mounted a vibratory hopper 21 for containing great number of circular workpieces or so-called billets l. The billets l are arranged within the hopper 21 into a row of aseries of aligned billets and are successively delivered therefrom into a curved chute 22 through which the billets are passed to a vertical toothed wheel 23 of billet feeding means which in turn guide and feed the billets into a vertical conduit 24 in which the billet are momentarily stacked.

The stacked billets I are then removed from the bottom end of the conduit 24 in successive order beginning with the lowermost one of the stacked billets by a series of teeth 25 fon'ned on the periphery of a billet feeding turret 26. The removed billets are moved together with the teeth25 of the turret 26 to a position A in which the billets are successively released from the teeth into dies 3 disposed in series along the peripheral edge of a turn table 27. In other words, the arrangement is such that the turret 26 is rotated in a direction opposite to the direction of rotation of the turn table 27 as shown by arrows in FIG. 2 and that the pitch of each adjacent pair of teeth 25 is the same as the pitch of each adjacent pair of dies 3.

The turn table 27 has a generally I-shaped axial section formed of a pair of upper and lower horizontal discs and a vertical column interconnecting the two discs. The lower disc is provided with a plurality of dies 3 disposed at a uniform interval adjacent the peripheral edge of the disc. The upper disc is provided adjacent the peripheral edge with a corresponding number of ram mechanisms 11 in axial alignment with respective dies 3 as will be seen in FIG. 1-.

The billets fed to the turn table 27 at the position A in FIG. 2 will be moved to a position B as the table is rotated. At the position B. the ramming mechanisms 11 are successively brought into vertical or axial alignment with the ramming roll 9 and are forced thereby to move downwardly so that the punches 2 on the lower ends of the ramming mechanisms are caused to cooperate with the corresponding dies 3 to form bil-, lets I into cylindrical hollow articles I. I

The hollow articles 1 thus formed are then successively moved together with the turn table 27 to a position C in which the articles are removed from the punches 2 by strippers to be described later and are delivered away from the turn table 27.

All of the operative motions of the apparatus is provided by a motor 28 the output of which is transmitted through a pair of gears 29 and 30. A part of the motor output is transmitted by a pulley and flywheel 32 and a gear to a crank shaft 8 having the ramming roll 9 mounted thereon at an intermediate portion thereof. A handle or wheel 31 is provided for adjusting the height of the ramming roll 9.

A further detailed description will be made with respect to driving force transmission mechanism, ram mechanisms and turn table which constitute the primary portions of the apparatus. With reference to FIG. 3, the torque of the motor 28 is transmitted from a pulley 33 thereof through an endless belt 34 to the pulley and flywheel 32 of a first intermediate shaft 35. The pulley and flywheel 32 is provided with an integral clutch 36, FIG. 4, the torque of which is transmitted to a second intermediate shaft 39 through gears 37 and.38 and to the crank shaft 8 through the gears 37 and 40.

The torque is further transmitted from the second intermediate shaft 39 and through a pair of bevel gears 41 and 42 and a vertical shaft 43 to the gear 29 which is in meshing engagement with the teeth 30 formed on the peripheral surface of the turn table 27, as shown in FIG. 4.

The ramming roll 9 is rotatably mounted on the eccentric or crank portion of the crank shaft 8 with a bushing 44 interposed therebetween, as shown in FIG. 3. The crank shaft 8 has its opposite ends 45 and 45' received in eccentric bushings 46 and 46'.respectively, which are supported by bearings 47 and 47' formed in the machine frame. The eccentric bushings have their inner ends formed with integral worm wheels 46a and 46a' in meshing engagement with worms 48 and 48' which are adapted to be rotated by the adjusting wheel 31. i

As previously described, the turn table 27 has a generally I- shaped axial section and has its upper disc 49 provided therein with a plurality of cylinders 50 for supporting the ramming mechanisms 1 l. A pair of sleeves 51 and 51' are fitted into the upper and lower ends of each cylinder 50. A punch holder 52 slidably extends through the sleeves 51 and 51'. A coil spring 54 is housed within each cylinder 50 and has one or upper end in abutting engagement with a shoulder 53 on the cooperating punch holder 52 so that the latter is biased upwardly by the coil spring and normally held in this position. Each of the punches 2 is rigidly secured to and mounted on one punch holder 52 by means of a nut 55.

Each punch holder 52 has a roller 56 mounted thereon by means of a bracket 57 which is secured to the upper end of the holder 52. The roller 56 is received in and guided by an annular camming groove 15 formed in the outer peripheral surface of a cylindrical cam member 14 which is fixedly mounted on the upper end portion of a main shaft 16. At the portion of the cam groove 15 adjacent the ramming roll 9, the cam groove 15 is widened or, in other words, the cam surface of the cam groove is curved or recessed downwardly so as to enable the rollers 56 of the ramming mechanisms 11 to be moved downwardly when the ramming mechanisms are brought into axial alignment with the roll 9 and downwardly driven thereby. On the other hand, the lower disc of the turn table 27 comprises, in the illustrated embodiment, two disc members 58 and 58. This arrangement is employed from the viewpoint of manufacture. The first disc member 58 is provided therein with a plurality of die bearings 59 each disposed in vertical alignment with one of the punches 2. Each die bearing 59 is of a larger diameter than that of dies 3 and is associated with means 60 for adjusting and positioning an associated die 3.

The second disc member 58' is provided with a toothed wheel I 61 fixed to the lower part of the peripheral surface of the member 58'. The toothed wheel 61 is in meshing engagement with a gear for driving the billet feeding turret 26 in synchronized relationship with the turn table 27. I

Means 62 is provided on a table surface 63 of the machine 7 frame 20 to bear against the turn table 27. Specifically, the

bearing means 62 has bearing members 64 and thrustbearing member 65 for rotatably supporting the turn table 27.

With the above-described construction, the billets 1 in the hopper 21 are successively fed through the chute 22, toothed wheel 23, conduit 24 and billet feeding turret 26 to the turn table 27 at the position A in which the successive billets I are fed into series of dies 3 on the turn table 27 which carries the billets to the position B in which the series of billets are worked one at a time by instantaneous impact extrusion into cylindrical hollow articles 1' which are then conveyed by the turn table 27 to the position C in which the articles 1 are successively removed off the table. Thus, the apparatus of the present invention is adapted for high speed feeding of the billets.

As the respective ramming mechanisms are driven one after another by the ramming roll as the turn table is rotated, it is sufficient for each punch to have only the stroke substantially of an amount required for the pressing of billets. Each of the punches is not required to have its stroke variable for the removal of worked articles however deep or long the latter may be.

Referring now to FIGS. 5, 6 and 7, a description will be made with respect to the billet feeding section of the apparatus. The series of billets l which have been arranged in row within the hopper 21 and fed by gravity through the inclined chute 22 to the end thereof are pushed and removed away off the chute one after another by respective teeth 70 of the toothed wheel 23 rotating in a vertical plane. The pushed billets 1 are fed into a guide 72 in the form of an arcuate pipe having therein a slot 71 for allowing the teeth 70 of the toothed wheel 23 to be moved therethrough. The billets are then fed into and stacked within the conduit 24 which is connected to the bottom end of the guide 72 and also has a slot for pennitting the teeth 70 to be moved therethrough. The bottom end of the conduit 24 terminates in a small distance from the horizontal plane in which the teeth 25 of the turret 26 for feeding the billets l to the dies 3 are moved along an arcuate path (see FIG. 6), the teeth 25 being of a thickness less than that of the billets. Thus, the billets 1 stacked within the conduit 24 are successively removed and delivered from the bottom end thereof one after lower one by the rotational movement of the successive teeth 25 with the delivered billets being held in horizontal positions.

The toothed wheel 23 has its shaft 73 to which the torque of an output shaft 75 of a motor and speed reduction mechanism 74 is transmitted through further reduction gears in the firm of a pinion 76 and a gear 77 as shown in FIG. 7. The shaft 73 is joumaled by means of a pair of bearings 78 and 78' on a base 79. The rotation of the shaft 73 is indirectly transmitted therefrom to the toothed wheel 23 by means ofa compression coil spring 80 extending around the shaft 73, a friction disc 81 urged by the spring 80 into frictional engagement with the outer surface of the toothed wheel 23, and a nut 82 for retaining the spring 80 and adjusting the pressure thereof against the toothed wheel 23. Thus, it will be appreciated that, under the overload condition, i.e., when the conduit 24 is filled with a series of billets 1, only the shaft 73 is driven but the torque of the shaft is not transmitted to the toothed wheel 23.

With the above-described arrangement of the billet feeding section, a series of billets 1 arranged in contact with each other in a row along the inner peripheral surface of the hopper 21 and passed through the chute 22 are fed by the toothed wheel 23 into the conduit 24 is stacked relationship and are then removed from the conduit 24 one after lower one by the billet feeding turret 26 and are fed thereby onto the turn table 27 in an accurated and reliable manner. The hopper 21 may be an oscillatory parts feeder.

It will therefore be appreciated that it is not required to manually feed billets 1 to the dies 3, nor is it required to synchronize the rotation of the toothed wheel 23 with that of the feeding turret 26. In addition, the apparatus is advantageous in that, since the feeding of billets is performed not by reciprocal motion but by rotary movement, the feeding can be carried out at a higher speed and in a reliable manner.

Referring now to FIGS. 8, 9 and 10 of the drawings, a description will be made in further detail with respect to the mechanism for adjusting the height of the ramming roll 9. The latter is to downwardly force the ramming mechanisms 11 of predetermined lengths by the peripheral surface of the roll 9 so that the driven ramming mechanisms are operable to work or press and shape billets 1 into cylindrical hollow articles 1'. Since the height or level at which the ramming roll 9 is positioned will influence the thickness of the bottom of a worked hollow article 1 the positioning of the ramming roll 9 must be precisely adjusted even during operation.

For this purpose, the wheel 31 for adjusting the height of the ramming roll 9 is rotatably mounted on the wall of the machine frame 20 as shown in FIGS. 1 and 9. As will be seen in FIG. 8, the wheel 31 has its shaft terminating in a gear 91 which is in meshing engagement with a pair of gears 92 and 92 mounted on one ends of shafts 93 and 93', respectively. These shafls have their other ends provided with the aforestated worms 48 and 48' which are in meshing engagement with the worm wheels 46a and 46a of the eccentric bushings 46 and 46', as described in reference to FIG. 3.

As shown in FIG. 9, a bracket member 94 is supported from the machine frame for rotatably supporting the opposite ends of the shafts 93 and 93' and the portion of the shaft 90 adjacent the gear 91 thereon. Adjacent the outer end of the shaft 90 on which the wheel 31 is mounted, a ratchet wheel 95 is mounted on the shah 90 for cooperation with a click 96 so as to fix the shaft 90 at an adjusted position of its rotation. The click 96 has an arm of a resilient material. The portion of the shaft adjacent the ratchet wheel 95 is rotatably supported by a bearing 97 which is mounted on the machine frame 20.

With the mechanism for adjusting the height of the ramming roll being designed to have the above-described arrangement, it is possible for the operator to finely adjust the height of the ramming roll so that finished products or hollow articles have bottom walls of precisely controlled thickness. The smaller is the eccentricity e between the axes of the crank shafi land the eccentric bushing 46 and 46', the greater is the preciseness in the adjustment of the ramming roll 9 and thus in the control of the thickness of the bottom walls of hollow articles. The adjusting mechanism employed in the apparatus of the present invention is remarkably simplified in both of construction and manipulation as compared with other type of adjusting mechanism which is designed to adjust respective ramming mechanisms. In addition, the adjusting mechanism of the present invention can be operated even during the operation of the apparatus.

With reference to FIGS. 11, 12 and 13, a description will be made with respect to the strippers 17 for removing formed hollow articles 1 from punches. As will be seen in FIGS. 1 and 11, a plurality of stripper holders 100 are secured by screws 108' to brackets 109 which in turn are secured to the intermediate cylindrical portion of the turn table 27 by screws 108. The strippers 17 correspond in number to the punches 2 attached to the ramming mechanisms 11 so that each of the strippers cooperates with one of the punches. As'will be best seen in FIG. 12, each stripper holder 100 is formed therein with a circular hole 100' in which a plurality of stripper pieces 101 each of a fan shape are arranged in such a manner as to form a flat annular ring.

As will be seen in FIGS. 11 and 13, each of the stripper pieces 101 is formed with a groove 102 of substantially semicircular cross-section in the peripheral outer surface of the piece 101 so that the grooves 102 in the annularly arranged stripper pieces 101 form an annular groove in which is received a ring-like spring 103 for radially inwardly biasing the stripper pieces 101 to gather them together when some of the segments 101 are shifted outwardly and a gap is formed between each adjacent pair of the segments. An annular member 104 is mounted by screws 105 on the bottom surface of each stripper holder 100 so as to support the stripper pieces 101 in position.

An annular space indicated by f is defined between the hole 100' and the peripheral outer surface of the annularly assembled stripper pieces 101, as shown in FIG. 12. A spring 106 of generally triangular shape is mounted in the annular space for centering the ring of the stripper pieces 101 within the hole 100'. The ring of the stripper segments 101 has a central opening 107 of a diameter which causes the peripheral edge of the opening 107 to closely contact the peripheral surface of each punch 2 when it is passed therethrough. By the resiliency of the centering spring 106, the central opening 107 is normally held in coaxial relationship with the hole 100 in the stripper holder 100 and, even if the associated punch 2 should laterally displace the stripper pieces 101 to cause the central opening 107 to be brought into an eccentric position relative to the hole 100', the stripper pieces are easily movable so as not to cause any bending stress in the punch 2.

A hollow article 1' formed from a billet l by impact extrusion is kept in engagement with the punch 2 and, when the corresponding punch holder 52 is moved upwardly by the action of the cam groove in the cam member as the turn table 27 is rotated, the hollow article 1 is also moved upwardly together with the punch 2 until the upper edge of the article abuts and. is stopped by the undersurface of the ring of the stripper pieces 101 at a portion adjacent the peripheral edge of the central opening of the ring. Thus, the article 1' is stripped off the punch 2..The latter is further moved upwardly untill the lower end thereof is moved past the central opening 107 of the stripper pieces 101 so as to assure complete removal of the article 1' from the punch2. It is required that the punch 2 be lowered again into the central opening of the stripper pieces 101. In order to facilitate easy insertion of the punch 2 into the opening 107, the stripper pieces 101 are shaped such that the peripheral edge of the opening is upwardly divergent to providea trumpet-like shape in axial section, as shown in FIGS. 11 and 13.

In the case where a punch should be broken or become dull and it is required to replace the punch with another one, the operator is not required to lift the corresponding ramming mechanism 11 in its entirety but is only needed to unscrew the associated nut 55 and cause the punch 2 to be inclined in a manner as shown in FIG. 13 for easy dismounting of the punch from the punch holder 52. When the punch 2 is removed off the central opening 107, the punch being removed causes some of the stripper pieces 101 to be radially outwardly displaced against the centering spring 106 for thereby allowing the punch to be easily removed from the apparatus. It is for this reason that the annular space f is left between the annularly assembled stripper pieces 10] and the hole 100'.

It will be appreciated that the strippers of the abovedescribed arrangement is advantageous in that a set of stripper pieces is normallyheld in a fixed position with respect to the associated stripper holder. In addition, even if the stripper pieces are displaced with respect to the associated punch, the pieces do not impart large bending stress to the punch but well accommodate the same. Moreover, the unique arrangement of the stripper facilitates easy replacement of punches.

' Referring next to FIGS. 14 and 15, a description will now be made with respect to the arrangement for adjusting the positions of the dies 3. The impact extrusion process requires extremely accurate alignment between a punch and a die since, if they are not coaxial with one another, they produce hollow articles having varing wall thickness. In order to meet with the requirement, the apparatus of the invention employs means for adjusting the positions of the dies 3 of the arrangement which will be described hereinunder.

Each of the dies 3 has a substantially cylindrical peripheral surface to which forces are exerted in radially inward directions at three positions of the surface angularly spaced about l. Namely, the adjusting or centering means are provided for each of the dies 3. Each die adjusting or positioning means includes a central positioning bolt 110 mounted on a fixed block 111 for forward and rearward adjusting movement relative to the block, On the opposite sides of the bolt 110, a pair of positioning bolts 1 l2 and 112' are also mounted on the block 111. The bolts 1 12 and 112' are of similar construction and it will be sufficient to describe one of them.

The positioning bolt 112 has its forward end threadably engaged with a cylindrical nut 1 13 so that the rotation of the bolt 112 will cause the nut 113 to be moved forwardly or rear wardly. The nut 113 has a pivot pin 114 by which a generally V-shaped lever or arm 115 is pivotally mounted on the nut 113. The arm 116 is also pivotally supported by a pin 116 which is fixed by the lower disc 58 of the turn table 27 and by a cover 117. The V-shaped arm 115 has a projection 118 adjacent the associated die 3. With the above arrangement, the rearward movement of the bolt 112 will cause the V-shaped am 115 to be rotated about the pin 116 so that a radially inward pressure force is applied by the projection 118.

A plate 119 is provided to retain a flanged portion of the positioning bolt 112 between the plate 119 and the fixed block 111 so that the bolt is held against axial movement and that only rotational movement is imparted to the bolt.

The similar parts associated with the other positioning bolt 112' are indicated by similar numerals with primes The afore-stated die bearing 59 is disposed under the corresponding die 3 and has a diameter somewhat greater than that of the die 3. The bearing 59 is received in an axial hole 121 extending through the first disc member 58 of the lower disc of the turn table 27 and is supported by the top surface of the second disc member 58. The die bearing 59 is made of a steel which is somewhat softer than the materials from which the disc member 58' and the dies 3 are made, respectively, so that the die bearing undertakes cumulated deformation after the operation of a certain amount of time. When the die bearing 59 is deformed to some extent, it may be replaced by another one so that the associated die 3 may be held in position, The deformation produced in the die bearing 59 will prevent the disc member 58 from becoming damaged in av shorter time.

The three positioning bolts are provided to extend in parallel relationship with each other. The use of the V-shaped arms 1 15 and 1 15' makes it possible to arrange the positioning bolts in the above manner so that the three positioning bolts can be manipulated on one side of an associated die. Thus, the die positioning means of the present invention are greatly simplified in operation as compared with conventional device of this kind employing positioning bolts which are angularly spaced l20 with respect to each other and, thus, are required to be manipulated on threesides of an associated die. Moreover, the bell crank mechanisms employed in conventional die positioning devices are required to be associated with fixing blocks formed with longer holes through which bolts extend, the longer holes being designed from theconsideration of bending of the bolts. The die positioning arrangement of the present invention does not require longer holes and are intended to impart to the positioning bolts 112 and 112 the tension forces which tend to produce force components to deform the bolts toward an associated die for thereby preventing the bolts from becoming loosed.

Referring further to FIGS. 16, 17 and 18, description will be made with respect to the heads of the ramming mechanisms 11 employed in the apparatus of the present invention. As

having been discussed in reference to FIGS. 1 and 3, the head of each ramming mechanism 11 is subjected to rolling and sliding contact by the ramming roll 9 so as to receive therefrom a greater magnitude of pressure force. Thus, the top of the ramming mechanism head is subjected to wear. It is preferred that the ramming roll 9 be made from a larger wearresistant material and, in addition, the roll 9 be treated with wear-resistant heat treatment. The head of each ramming mechanism 11 is preferably designed to be suited for easy replacement.

The figures illustrate a preferred construction of the head of each ramming mechanism. Specifically, the punch holder 52 is formed at the top with an axial bore into which is fitted a ram head member 131 having a flat top surface. The head member 131 and the abovementioned bracket 57 are secured to the top of the punch holder 52 by means of four conventional sets screws or bolts 132. The bracket 57 has an integral upwardly projecting part adjacent and facing the tum'table 27. This'part of the bracket supports a roller 56 which is rotatably mounted on a lateral pin 134 extending through the i upward projection and fixed thereto by a nut 133. The roller 56 may be mounted on the pin 134 through an anti-friction means such as needle bearing (not shown).

Each of the rollers 56 is in rolling engagement with the cam groove fonned in the peripheral surface of the cam member 14 as shown in FIG. 3 and is moved along the cam groove as the turn table 27 is rotated so that the roller 56 is reciprocally moved upwardly and downwardly as guided by the cam groove to cause the associated punch 2 to have gentle upward and downward strokes of movements excepting for the time the punch is actuated by the camming roll 9 to work a billet 1. This actuation takes place when the roller 56 is moved to the downwardly recessed portion of the cam groove 15.

The roller bracket 57 is provided with a shaft 135 extending in parallel with the punch holder 52, as shown in FIG. 18. The bottom end (not shown) of the shaft 135 is fitted into a bore (not shown) in the upper disc 49 of the turn table 27 so that the shaft 135 prevents the assembly of the punch holder 52 and the blacket 57 from being loosely rotated about the axis of the holder 52 to thereby ensure easy detachment of the four bolts 132 for the replacement 'of a worm head 131 with another one.

The ramming mechanisms 11 will then be described in connection with the ram head section. As previously been described with reference to FIG. 3, the inner surface of each of the cylinders 50 provided in the upper disc 49 of the turn table 27 has the upper and lower end portions into which the two sleeves 51 are fitted so as to slidably support the associated punch holder 52. The innersurface of the cylinder 50 is radially outwardly expanded at the portion between the two sleeves 51 to define a cylindrical space 136 of a diameter somewhat greater than that of the sleeves 51. The space 136 houses a coil spring 54 having its upperend bearing against the shoulder 53 on the punch holder 52.

The punch holder 52 supports at the top end the roller 56 through the bracket 57 while the bottom end of the holder is in engagement with the nut 55 for attaching the punch 2 to the holder 52. Thus, each of the ramming mechanisms or the assemblies 11 is of a substantial weight. The coil spring 54 is provided to serve to take up at least a part of the weight of the associated ramming mechanism 11 so that the latter is capable of being smoothly moved up and down by the action of the cam groove 15 which the turn table 27 is rotated. It will be appreciated that the coil spring 54 serves to reduce the friction produced between the roller 56 of the associated ramming mechanism 11 and the cam surface of the cam groove 15 in that the spring partly supports the ramming mechanism. This feature of the invention contributes to considerable reduction or decrease in the torque required to drive or operate the apparatus. 1

The space 136 is hermetically sealed from the atmosphere so that the ramming mechanism 11 is subjected to positive lubrication by a lubricant liquid introduced into the space through a lubricant passage 137. The latter may also be utilized to supply air under pressure therethrough into the space 136 so that the punch holder 52 may act as an air-actuated piston which would be operative to partly support the ramming mechanism 11. This additional feature of the invention is advantageous in that the ramming mechanisms 11 are at least partly supported by pressurized air within the spaces 136 so that the torque required to drive the turn table 27 is minimized for the reason similar to that discussed in connection with the coil spring 54. Moreover, in the replacement of a worn punch with another new one or in other similar operations, the punch holder 52 with the associated roller 56 having been removed off may be easily lifted by manual operation since the punch holder is at least partly supported by the associated coil spring 54 and the pressurized air within the space 136.

As described in the above, the apparatus according to the present invention provides considerable advantages in that the apparatus is operative to produce hollow articles from billets or circular work-pieces of a metal at a remarkably increased efficiency and, in addition, is suited for high-speed massproduction of such hollow articles. 7

What is claimed is:

1. An apparatus for producing open-topped hollow articles from circular work-pieces of a metal, comprising a turn table having a plurality of dies mounted thereon adjacent the periphery of said turn table by means of die position adjusting means, said turn table also having ramming mechanisms each having a punch disposed above one of said dies for cooperation therewith; a turret for receiving such work-pieces supplied from a hopper by feeding means and for successively feeding the received work-pieces to said turn table; a ramming roll for downwardly moving said ramming mechanisms to cause said punches to cooperate with corresponding dies to form said work-pieces therein into open-topped hollow articles during rotation .of said turn table; cam means for lifting the ramming mechanisms after their forming operations; and stripping means each comprising a stripper for removing a formed hollow article from an associated punch.

2. An apparatus according to claim 1, comprising means for adjusting the height of said ramming roll, said adjusting means includes a height-adjusting wheel rotatably mounted on the frame of said apparatus, a worm adapted to be operated. by said wheel, and worm wheels in meshing engagement with said worm, said worm wheels having integral bushings supporting a crank shaft at the opposite end portions thereof, said bushing being eccentric with respect to the axes of said end portions of said crank shaft, said ramming roll being fixedly mounted on said crank shaft at the portion intermediary of the opposite ends thereof.

3. An apparatus according to claim 1, in which each of said stripping means has a plurality of stripper pieces arranged in an annular assembly having an inner peripheral edge for close contact with the peripheral surface of the forward end of an associated punch, resilient means extending around the outer peripheral surface of said annular assembly for radially inwardly biasing said stripper pieces, a stripper holder having formed therein a circular hole, and a centering spring for mounting and centering said assembly in said hole, said hold being sized such that a space is defined between said hole and said assembly.

4. An apparatus according to claim 1, in which each of aid ramming mechanisms comprises a cylinder within said turn table, a punch holder having a forward end supporting a punch, said holder being movably positioned in said cylinder, and means operative to at least partly support said punch holder so that the latter is biased upwardly.

5. An apparatus according to claim 1, in which each of said die position adjusting means comprisesa block membermounted on the lower disc of said turn table, three positioning bolts extending through said block member with the heads of said bolts being arranged in a row on one surface of said block member, the central positioning bolt having its forward end in direct pressure-engagement with the peripheral surface of an associated die, each of the other positioning bolts having a generally V-shaped lever mounted in such a manner that the rotation of said the other bolt in one direction causes said lever to be pivotally moved to exert a radially inwardly directed pressure force against the peripheral surface of said die at a point angularly spaced from the point of contact of said central bolt with said peripheral surface.

6. An apparatus according to claim 1, in which each of said ramming mechanisms has a ram head member of a material softer than the material from which said ramming roll is made,

and a bracket member secured with said ram head member to the top of said punch holder by means of bolts, said bracket member rotatably supporting a roller in rolling engagement with said cam means, said ram head member being adapted to be rammed by said ramming roller when said head member is brought into alignment with said ramming roller by the rotation of said turn table.

7. An apparatus for producing open-topped hollow articles from circular workpieces of a metal, comprising a hopper for containing such workpieces; a chute for delivering the workpieces from said hopper in aligned relationship with each other; means adjacent the forward end of said chute rotatable in a vertical plane and having teeth on the peripheral edge for successively removing the work-pieces, from said chute and feeding them into a vertical conduit; a turret rotatable in a horizontal plane and having teeth on the peripheral edge each for removing one workpiece from the bottom end of said vertical conduit with the removed workpiece held in horizontal position and for feeding said removed workpiece to a turn table, said turn table having a plurality of dies mounted thereon adjacent the periphery of said turn table by means of die posimechanisms after their forming operations; and stripping means each comprising a stripper for removing a formed hollow article from an associated punch.

l i t i l 

1. An apparatus for producing open-topped hollow articles from circular work-pieces of a metal, comprising a turn table having a plurality of dies mounted thereon adjacent the periphery of said turn table by means of die position adjusting means, said turn table also having ramming mechanisms each having a punch disposed above one of said dies for cooperation therewith; a turret for receiving such work-pieces supplied from a hopper by feeding means and for successively feeding the received work-pieces to said turn table; a ramming roll for downwardly moving said ramming mechanisms to cause said punches to cooperate with corresponding dies to form said work-pieces therein into opentopped hollow articles during rotation of said turn table; cam means for lifting the ramming mechanisms after their forming operations; and stripping means each comprising a stripper for removing a formed hollow article from an associated punch.
 2. An apparatus according to claim 1, comprising means for adjusting the height of said ramming roll, saId adjusting means includes a height-adjusting wheel rotatably mounted on the frame of said apparatus, a worm adapted to be operated by said wheel, and worm wheels in meshing engagement with said worm, said worm wheels having integral bushings supporting a crank shaft at the opposite end portions thereof, said bushing being eccentric with respect to the axes of said end portions of said crank shaft, said ramming roll being fixedly mounted on said crank shaft at the portion intermediary of the opposite ends thereof.
 3. An apparatus according to claim 1, in which each of said stripping means has a plurality of stripper pieces arranged in an annular assembly having an inner peripheral edge for close contact with the peripheral surface of the forward end of an associated punch, resilient means extending around the outer peripheral surface of said annular assembly for radially inwardly biasing said stripper pieces, a stripper holder having formed therein a circular hole, and a centering spring for mounting and centering said assembly in said hole, said hold being sized such that a space is defined between said hole and said assembly.
 4. An apparatus according to claim 1, in which each of aid ramming mechanisms comprises a cylinder within said turn table, a punch holder having a forward end supporting a punch, said holder being movably positioned in said cylinder, and means operative to at least partly support said punch holder so that the latter is biased upwardly.
 5. An apparatus according to claim 1, in which each of said die position adjusting means comprises a block member mounted on the lower disc of said turn table, three positioning bolts extending through said block member with the heads of said bolts being arranged in a row on one surface of said block member, the central positioning bolt having its forward end in direct pressure-engagement with the peripheral surface of an associated die, each of the other positioning bolts having a generally V-shaped lever mounted in such a manner that the rotation of said the other bolt in one direction causes said lever to be pivotally moved to exert a radially inwardly directed pressure force against the peripheral surface of said die at a point angularly spaced 120* from the point of contact of said central bolt with said peripheral surface.
 6. An apparatus according to claim 1, in which each of said ramming mechanisms has a ram head member of a material softer than the material from which said ramming roll is made, and a bracket member secured with said ram head member to the top of said punch holder by means of bolts, said bracket member rotatably supporting a roller in rolling engagement with said cam means, said ram head member being adapted to be rammed by said ramming roller when said head member is brought into alignment with said ramming roller by the rotation of said turn table.
 7. An apparatus for producing open-topped hollow articles from circular workpieces of a metal, comprising a hopper for containing such workpieces; a chute for delivering the workpieces from said hopper in aligned relationship with each other; means adjacent the forward end of said chute rotatable in a vertical plane and having teeth on the peripheral edge for successively removing the work-pieces from said chute and feeding them into a vertical conduit; a turret rotatable in a horizontal plane and having teeth on the peripheral edge each for removing one workpiece from the bottom end of said vertical conduit with the removed workpiece held in horizontal position and for feeding said removed workpiece to a turn table, said turn table having a plurality of dies mounted thereon adjacent the periphery of said turn table by means of die position adjusting means, said turn table also having ramming mechanisms each having a punch disposed above one of said dies for cooperation therewith; a ramming roll for downwardly moving said ramming mechanisms to cause said punches to cooperate with corresponding dies to form said workpieces thereIn into open-topped hollow articles during rotation of said turn table; cam means for lifting the ramming mechanisms after their forming operations; and stripping means each comprising a stripper for removing a formed hollow article from an associated punch. 